Material fob shoe stiffenees



Reissuegl May 25, 1943 MATERIAL FOR SHOE STIFFENERS lingo Boeddinghaus, Newburgh. N. Y., asslgnor to American Felt Company, New York, N. Y., a corporation of Massachusetts 7 No Drawing. Original No. 2,293,214, dated omber 13, 1942, Serial No. 351,231, August a. 1940. I Application for reissue February 28, 1943, Serial 4 can. (or. 36-68) This application is a continuation-in-part of my co-pending application Serial No. 328,768. filed April 9, 1940, for Felt-like fabrics and methd of producing the same, which inturn is a continuation-in-part of my application Serial No. 211,926, filed June 4, 1938.

The invention of this present application relates to material for shoe stifieners. and has for its principal objects to provide an improved shoe stiffener capable of being made in a simpler-manher than prior shoe stifleners, easy to ship and handle, and easy to soften and bend into the appropriate curved shape for application to the shoe.

Other objects of invention and features of advantage and utility will be apparent from this specification wherein the invention is explained by way of example.

In a preferred example of the invention, material is prepared in a manner now to be described. A thorough mixture of from 30%, or preferably more than 30%, up to approximately 50% synthetic thermoplastic fibers and the remainder of cotton fibers (preferabty about 40% synthetic fibers and 60% cotton fibers) is prepared by subjecting both kinds of fibers together to a picking operation, to a blowing operation (usually repeated :1- number of times), and'io a carding operation (preferably at least twice) The effect of these operations is to produce a thin carded web in which the thermoplastic fibers formly distributed throughout the web. A plurallty of these webs are then superposed to provide a batt of material weighing, for example, ounces per square yard, the exact weight depending upon the requirements of the trade.

The batt is then subjected to a hot-pressing operation to bond the thermoplastic fibers. For this purpose the apparatus disclosed in my copending application for Bonding sheet material, filed July 30, 1940, Serial No. 348,371, may be employed. In this hot-pressing operation, the batt oi. material is subiected to a pressure of approximately 700 pounds per square inch between press plates that are heated to approximately 300 F. The material is protected from adhesion tothe press plates by suitable nonthcrmoplastic textile aprons during the pressing.-

The resulting product is a'thin sheet of approximately .055 to .065 inch thlcknessof stillhas and bendability comparable to shoe stiffeners customarily used. This sheet material can be cut to the usual shape of a shoe stiffener.

for example, to the shape of a box toe stifiener, and its edges skived in the customary manner.

, The shoe stiffener produced by this procedure thus comprises a sheet in which the req-. uisite stiilness and strength .is secured by means of the fibrous material or which the sheet is composed, so that no filling or weighting material, such as wax, rosin or the like, need be employed.

The s'tifleners. produced as described, can be shipped in a dry state to the shoe factory and can be. stored for as long as desired without danger of deterioration. To prepare the stifienera for use they can be softened either by application of heat or by application ofa suitable volatile solvent, and bent to the desired shape on the last. Inusing a solvent for the P rp se of softening the stiffener-s, there should be applied only sufiicient solvent action to soften the material and not to disintegratethe thermoplastic fibers of the material.

As the thermoplastic fiber, there may be employed a considerable range of fibrous material. the requirements being in general that these thermoplastic fibers shall be sufllciently long, strong and pliable to withstand the carding operation and be capable of softening sufliciently to bond with one another at temperatures sufllciently low not to harm the cotton fibers. A preferred thermoplastic fiber for this purpose has been found to be a" plasticized acetate rayon, available under v the trade name of Tenite. Other suitable fibers are:

1. Vinylite, also known under the trade name of "Vinyon, a conioint polymer of a vinyl halide with a vinyl ester of a lower molecular aliphatic acid as vinyl acetate, referred to at times as vinyl resin fibers.

- 2. Methyl methacrylate resins such as are available under the trade name of "Lucite."

3. "Nylon." 9. polyamide produced by the re- I action between a primary or a secondary diamine and either a dicarboxylic acid or an amideforming derivative of a dibasic carbolic acid.

I claim:

l. A shoe stiil'ener in the form of a sheet consisting of a carded mixture of from more than 30 per cent to approximately 50 per cent oi thermoplastic fibers and the remainder substansistlng of a carded mixture of approximately 40 35 ounces per square yard.

tore being bonded and compacted'toa still condition by hot pressure and being capable 01' being softened by the action oi heat or solvent.

3. A shoe stiilene'r m the form of a sheet con-' slstins oi a carded mixture of trom'more than 30 per cent to approximatel'ybi) per cent 01 thermoplastic fibers and the remainder substantially all cottonflbers. said mixture beingbonded and compacted to a stii! condition by not pressure, being capable of being .softened by the action of heat or solvent and weighing approximately per cent of thermoplastic fibers and approxi- 4. mm; m the mm of, a sheet conmately 60 per cent or cotton nbers. said mixsistins 1a carded mixture at irom 30 per cent to approximately-50 per cent-oi thermoplastic fibers-and the-remainder substan- 5 tially all cotton fibers. said mixture beinz'bond- 10 .065 inchin ed and compacted to a still condition by not pressure, and bein: capable oi being ssottened by the action-otheator solvent and sheet beinmappmxmately .055 inch'to approximately woo nonnnmomus. 

